Adsorption cooling system using metal organic frameworks

ABSTRACT

A highly adsorptive structure, includes: a substrate; and a metal-organic framework (MOF) comprising a plurality of metal atoms coordinated to a plurality of organic spacer molecules; wherein the MOF is coupled to at least one surface of the substrate, wherein the MOF is adapted for adsorbing and desorbing a refrigerant under predetermined thermodynamic conditions. The refrigerant includes one or more materials selected from the group consisting of: acid halides, alcohols, aldehydes, amines, chlorofluorocarbons, esters, ethers, fluorocarbons, perfluorocarbons, halocarbons, halogenated aldehydes, halogenated amines, halogenated hydrocarbons, halomethanes, hydrocarbons, hydrochlorofluorocarbons, hydrofluoroethers, hydrofluoroolefins, inorganic gases, ketones, nitrocarbon compounds, noble gases, organochlorine compounds, organofluorine compounds, organophosphorous compounds, organosilicon compounds, oxide gases, refrigerant blends and thiols.

RELATED APPLICATIONS

This is a continuation-in-part of U.S. application Ser. No. 13/457,331,filed Apr. 26, 2012, which is incorporated herein by reference and towhich the benefit of priority is hereby claimed.

The United States Government has rights in this invention pursuant toContract No. DE-AC52-07NA27344 between the United States Department ofEnergy and Lawrence Livermore National Security, LLC for the operationof Lawrence Livermore National Laboratory.

FIELD OF THE INVENTION

The present disclosure relates to metal organic frameworks (MOFs), andparticularly, to high-surface area MOFs as adsorbents for adsorptivecooling systems and methods of use thereof.

BACKGROUND

A significant amount of expensive electrical energy is used to aircondition and refrigerate commercial and industrial facilities andprocesses. For example, air conditioning and low temperaturerefrigeration is estimated to constitute 19% and 9%, respectively, ofall electrical energy consumed by commercial buildings. If concentratingsolar energy or other waste heat was recaptured or collocated with enduse, it could power thermally activated cooling systems andsubstantially reduce electrical power consumption.

While adsorption-based cooling and refrigeration systems are simple andeasy to maintain, today's systems are expensive and relativelyinefficient, requiring large footprints and high desorptiontemperatures. Therefore, it would be beneficial to reduce costsassociated with developing, manufacturing, and using highly adsorptivenanoporous materials for adsorptive cooling applications by using MOFsand substrate combinations which improves the adsorption/desorptionperformance of the structures produced, and enhances the mass-specificstored energy density by using lightweight materials.

Moreover, MOFs have been used in some adsortption cooling applications,such as disclosed in Henninger, et al., Journal of the American ChemicalSociety 131(8), 2776 (2009), where metal organic frameworks were usedfor adsorption and desorption of water. Although this is an adsorptivecooling system, it is only operative for adsorption cooling via water asan adsorptive cooling material, which limits application of MOFs towater-stable systems. Moreover, the arrangement of MOFs as adsorbentcooling systems may be improved over the conventional systems byincreasing accessible surface area for the MOF in the cooling system.Therefore, it would be beneficial to provide an improved adsorptivecooling system employing MOFs and capable of utilizing a variety ofheretofore undisclosed refrigerants, as well as providing an adsorptivecooling system employing MOFs to improve adsorptive cooling performanceby facilitating ingress and egress of refrigerant to and from theadsorptive MOF.

SUMMARY

In one embodiment, a product includes a highly adsorptive structure, andthe highly adsorptive structure includes: a substrate; and ametal-organic framework (MOF) including a plurality of metal atomscoordinated to a plurality of organic spacer molecules; where the MOF iscoupled to at least one surface of the substrate. The MOF is adapted foradsorbing and desorbing a refrigerant under predetermined thermodynamicconditions, the refrigerant being selected from the group consisting of:acid halides, alcohols, aldehydes, amines, chlorofluorocarbons, esters,ethers, fluorocarbons, perfluorocarbons, halocarbons, halogenatedaldehydes, halogenated amines, halogenated hydrocarbons, halomethanes,hydrocarbons, hydrochlorofluorocarbons, hydrofluoroethers,hydrofluoroolefins, inorganic gases, ketones, nitrocarbon compounds,noble gases, organochlorine compounds, organofluorine compounds,organophosphorous compounds, organosilicon compounds, oxide gases,refrigerant blends and thiols.

In another embodiment, an adsorptive cooling system includes: a firsthighly adsorptive structure positioned to receive thermal energy from athermal energy source, the first highly adsorptive structure includes: afirst substrate; and a first metal-organic framework (MOF) coupled tothe first substrate, the first MOF being adapted for adsorbing anddesorbing a refrigerant under predetermined thermodynamic conditions.Moreover the adsorptive cooling system includes a second highlyadsorptive structure positioned to receive thermal energy from thethermal energy source, the second highly adsorptive structure including:a second substrate; and a second MOF coupled to the second substrate andadapted for adsorbing and desorbing a refrigerant under predeterminedthermodynamic conditions. Moreover still the adsorptive cooling systemincludes a cooling unit; and a circulation system adapted forcirculating the refrigerant from at least one of the first highlyadsorptive structure and the second highly adsorptive structure to thecooling unit to provide cooling from the thermal energy source and toreturn the refrigerant from the cooling unit to at least one of thefirst highly adsorptive structure and the second highly adsorptivestructure, where the first and/or second substrate includes a pluralityof microchannels, where the microchannels are defined by at least one ofgrooves in a surface of the substrate nearest the MOF and surfaces of aplurality of microcapillaries of the substrate, where the microchannelsprovide ingress and egress paths for a refrigerant. The refrigerant isselected from the group consisting of: acid halides, alcohols,aldehydes, amines, chlorofluorocarbons, esters, ethers, fluorocarbons,perfluorocarbons, halocarbons, halogenated aldehydes, halogenatedamines, halogenated hydrocarbons, halomethanes, hydrocarbons,hydrochlorofluorocarbons, hydrofluoroethers, hydrofluoroolefins,inorganic gases, ketones, nitrocarbon compounds, noble gases,organochlorine compounds, organofluorine compounds, organophosphorouscompounds, organosilicon compounds, oxide gases, refrigerant blends andthiols.

In still another embodiment a method includes forming a MOF on thesubstrate to produce a product including a highly adsorptive structure,the highly adsorptive structure including: a substrate; and ametal-organic framework (MOF) including a plurality of metal atomscoordinated to a plurality of organic spacer molecules; where the MOF iscoupled to at least one surface of the substrate, and where the MOF isadapted for adsorbing and desorbing a refrigerant under predeterminedthermodynamic conditions.

Other aspects and embodiments of the present disclosure will becomeapparent from the following detailed description, which, when taken inconjunction with the drawings, illustrate by way of example theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 includes a schematic depiction of a metal organic frameworkhaving a plurality of pores and a refrigerant adhered thereto.

FIG. 2 depicts one of several various possible shapes of MOFs accordingto illustrative embodiments.

FIG. 3 depicts one of several various possible shapes of MOFs accordingto illustrative embodiments.

FIG. 4 depicts one of several various possible shapes of MOFs accordingto illustrative embodiments.

FIG. 5 depicts one of several various possible shapes of MOFs accordingto illustrative embodiments.

FIG. 6 depicts several examples of building units for MOFs, according toone embodiment.

FIG. 7 illustrates one embodiment of an adsorption-desorptionrefrigeration system (ADRS) constructed in accordance with the presentdescriptions, according to one embodiment.

FIG. 8 illustrates phase 1 of the (ADRS), according to one embodiment.

FIG. 9 illustrates phase 2 of the (ADRS), according to one embodiment.

FIG. 10 illustrates the ADRS during a low-temperature period, accordingto one embodiment.

FIG. 11 illustrates the predicted Langmuir adsorption isotherm for abetter refrigerant and adsorption-medium combination at varioustemperature levels, according to one embodiment.

FIG. 12 illustrates a refrigeration cycle, according to one embodiment.

FIG. 13 illustrates another embodiment of a solar poweredadsorption-desorption refrigeration system (ADRS) constructed inaccordance with one embodiment of the present disclosure.

FIG. 14 illustrates yet another embodiment of a solar poweredadsorption-desorption refrigeration system (ADRS) constructed inaccordance with the present disclosure.

FIG. 15A illustrates a substrate having a corrugated surface, accordingto one embodiment

FIG. 15B illustrates a substrate having a plurality of microchannelsarranged along a surface of the substrate, according to one embodiment.

FIG. 15C illustrates a substrate having a plurality of microchannelsarranged along a surface of the substrate, according to one embodiment.

FIG. 16A shows one arrangement for a plurality of microchannels arrangedalong a surface of the substrate, according to one embodiment.

FIG. 16B shows one arrangement for a plurality of microchannels arrangedalong a surface of the substrate, according to one embodiment.

FIG. 16C shows one arrangement for a plurality of microchannels arrangedalong a surface of the substrate, according to one embodiment.

FIG. 16D shows one arrangement for a plurality of microchannels arrangedalong a surface of the substrate, according to one embodiment.

FIG. 17 shows a flowchart of a method, according to one embodiment.

DETAILED DESCRIPTION

The following description is made for the purpose of illustrating thegeneral principles of the present disclosure and is not meant to limitthe inventive concepts claimed herein. Further, particular featuresdescribed herein can be used in combination with other describedfeatures in each of the various possible combinations and permutations.

Unless otherwise specifically defined herein, all terms are to be giventheir broadest possible interpretation including meanings implied fromthe specification as well as meanings understood by those skilled in theart and/or as defined in dictionaries, treatises, etc.

It must also be noted that, as used in the specification and theappended claims, the singular forms “a,” “an” and “the” include pluralreferents unless otherwise specified.

As used herein, the term “about” when combined with a value refers toplus and minus 10% of the reference value unless otherwise specified.For example, a temperature of about 50° C. refers to a temperature of50° C.±5° C., etc.

In one general embodiment, a product includes a highly adsorptivestructure, and the highly adsorptive structure includes: a substrate;and a metal-organic framework (MOF) including a plurality of metal atomscoordinated to a plurality of organic spacer molecules; where the MOF iscoupled to at least one surface of the substrate, and where the MOF isadapted for adsorbing and desorbing a refrigerant under predeterminedthermodynamic conditions. The refrigerant is selected from the groupconsisting of: acid halides, alcohols, aldehydes, amines,chlorofluorocarbons, esters, ethers, fluorocarbons, perfluorocarbons,halocarbons, halogenated aldehydes, halogenated amines, halogenatedhydrocarbons, halomethanes, hydrocarbons, hydrochlorofluorocarbons,hydrofluoroethers, hydrofluoroolefins, inorganic gases, ketones,nitrocarbon compounds, noble gases, organochlorine compounds,organofluorine compounds, organophosphorous compounds, organosiliconcompounds, oxide gases, refrigerant blends and thiols.

In another general embodiment, an adsorptive cooling system includes: afirst highly adsorptive structure positioned to receive thermal energyfrom a thermal energy source, the first highly adsorptive structureincludes: a first substrate; and a first metal-organic framework (MOF)coupled to the first substrate, the first MOF being adapted foradsorbing and desorbing a refrigerant under predetermined thermodynamicconditions. Moreover the adsorptive cooling system includes a secondhighly adsorptive structure positioned to receive thermal energy fromthe thermal energy source, the second highly adsorptive structureincluding: a second substrate; and a second MOF coupled to the secondsubstrate and adapted for adsorbing and desorbing a refrigerant underpredetermined thermodynamic conditions. Moreover still the adsorptivecooling system includes a cooling unit; and a circulation system adaptedfor circulating the refrigerant from at least one of the first highlyadsorptive structure and the second highly adsorptive structure to thecooling unit to provide cooling from the thermal energy source and toreturn the refrigerant from the cooling unit to at least one of thefirst highly adsorptive structure and the second highly adsorptivestructure, where the first and/or second substrate includes a pluralityof microchannels, where the microchannels are defined by at least one ofgrooves in a surface of the substrate nearest the MOF and surfaces of aplurality of microcapillaries of the substrate, and where themicrochannels provide ingress and egress paths for a refrigerant. Therefrigerant is selected from the group consisting of: acid halides,alcohols, aldehydes, amines, chlorofluorocarbons, esters, ethers,fluorocarbons, perfluorocarbons, halocarbons, halogenated aldehydes,halogenated amines, halogenated hydrocarbons, halomethanes,hydrocarbons, hydrochlorofluorocarbons, hydrofluoroethers,hydrofluoroolefins, inorganic gases, ketones, nitrocarbon compounds,noble gases, organochlorine compounds, organofluorine compounds,organophosphorous compounds, organosilicon compounds, oxide gases,refrigerant blends and thiols.

In still another general embodiment a method includes forming a MOF onthe substrate to produce the product including a highly adsorptivestructure, the highly adsorptive structure including: a substrate; and ametal-organic framework (MOF) including a plurality of metal atomscoordinated to a plurality of organic spacer molecules; where the MOF iscoupled to at least one surface of the substrate, and where the MOF isadapted for adsorbing and desorbing a refrigerant under predeterminedthermodynamic conditions.

A list of acronyms used in the description is provided below.

AC activated carbonADRS solar powered adsorption-desorption refrigeration systemBET Brunauer-Emmett-Teller theoryCFC chlorofluorocarbon

CMMD Condensed Matter and Materials Division (LLNL)

CRADA cooperative research and development agreement

DHS Department of Homeland Security

EDAX energy-dispersive analysis of x raysEER energy efficiency ratioESEM emission scanning electron microscopyHVAC heating, ventilation, and air conditioning

LLNL Lawrence Livermore National Laboratory MOF Metal Organic FrameworkNREL National Renewable Energy Laboratory

SEER seasonal energy efficiency ratioT&P temperature and pressureTEM transmission electron microscopyUHS ultrahigh surface (metal organic framework)

As used in this application, the term “Retractable Shade” means anylight blocking system adapted to selectively block energy from the sun.For example, the “retractable shade” can alternatively be a loweredshade, a shutter shade, an electronic light blocking system for blockingenergy from the sun, or any other system for blocking energy from thesun.

Highly Adsorptive Metal Organic Framework Materials and Methods ofFabrication

Metal organic frameworks (MOFs) with extremely high mass-specificsurface area (up to about 5000 m²/g) has been investigated for use insome embodiments described herein. MOFs are novel mesoporous materialswhich combine many interesting properties such as low mass densities,continuous porosities, high surface areas, high electricalconductivities, and excellent mechanical properties. The properties ofMOFs are derived from their microstructure, which is typically a networkof interconnected primary particles with characteristic diameters ofbetween about 3 nm and about 25 nm, though the dimensions could behigher and/or lower. The material forms macroscopic (for instance,mm-sized) monolithic bodies that support compressive stress and shearstress.

According to some embodiments, the properties of MOFs can be tailoredfor specific applications by controlling their morphology and/or byadding surface functionalities. The design of new porous MOF materialsholds technological promise for a variety of applications, includingcatalysis, hydrogen storage, and energy storage. The utility of thesematerials may be derived from their high surface areas, electricallyconductive frameworks, and chemical stability. MOFs are a unique classof porous materials that possess ultrafine cell sizes, continuousporosities, and low mass densities. These properties arise from theframework microstructure, a three-dimensional network of primary metalatoms and/or ions interconnected particles with diameters that can rangefrom a few nanometers to several microns

The skeletal structure of this material includes interconnectedmicron-sized organic ligands 104 that define a continuous macroporousnetwork 100 between nodes 102, substantially as shown in FIG. 1,according to one embodiment. This structural motif is likely responsiblefor the enhanced mechanical integrity of these MOF monoliths, bothbefore and after activation. Despite being macroporous, thepre-activated MOF still exhibits appreciable surface area due tomicroporosity within the organic ligands. In one embodiment, the network100 of organic ligands 104 and nodes 102 define a plurality of poresparticularly suitable for adsorbing and retaining a fluid such asrepresented by fluid particles 106 as shown in FIG. 1. Fluids capable ofadsorbing to the MOF include any suitable fluid such as a gas or aliquid, and preferably include refrigerant gases in some approaches. Inparticularly preferred approaches, the fluid particles 106 may beselected from a group as laid out below in Tables 1 and 2 and delineatedin paragraph infra.

Of course, MOFs may be constructed to produce a variety of forms, suchas several exemplary embodiments as shown in FIGS. 2-5. Moreover, MOFsmay be constructed from a plurality of small building units (SBUs) suchas depicted in FIG. 6, in some approaches.

In some approaches, the metal organic framework may have a mass-specificsurface area of greater than about 5000 m²/g.

In more approaches, the metal organic framework may include a network ofinterconnected primary particles, the primary particle having acharacteristic diameter of between about 3 nm and about 25 nm. Infurther approaches, the characteristic diameter may be between about3-10 nm, between about 5-15 nm, between about 12-25 nm, between about5-20 nm, etc. as would be understood by one having ordinary skill in theart upon reading the present descriptions.

In one embodiment, a highly adsorptive structure includes a substrateand a metal organic framework adhered to the substrate, wherein themetal organic may be formed on the substrate includes any formationprocess where a metal organic framework is formed directly on thesubstrate surface from constituent metal organic framework components asdescribed above.

Moreover, in various approaches the MOF is adapted for adsorbing anddesorbing a refrigerant under predetermined thermodynamic conditions. Asunderstood herein, thermodynamic conditions include pressure andtemperature. Preferably, adsorption/desorption temperatures should berelatively low, e.g. less than 90° C. in some embodiments. As will beunderstood by one having ordinary skill in the art upon reading thepresent descriptions, favorable thermodynamic conditions foradsorption/desorption depend on the particular combination of MOF andrefrigerant being employed.

In more approaches, the predetermined thermodynamic conditions are basedon an identity of each of: the plurality of metal atoms, the pluralityof organic spacer molecules, and the refrigerant. In particular,thermodynamic conditions for adsorption/desorption are generally afunction of the organic spacer and metal ions employed. Specificcombinations may be chosen to tailor different systems to individualrefrigerants and/or operating conditions as would be understood by theskilled artisan reading the present descriptions.

Moreover still, in additional approaches, the MOF is characterized by apore structure, wherein the pore structure is determined based on anidentity of each of: the plurality of metal atoms and the plurality oforganic spacer molecules. In particular, and as would be understood byone having ordinary skill in the art upon reading the presentdescriptions, pore size and structure, akin to thermodynamic conditionsfor adsorption/desorption, may be tailored to individual MOF/refrigerantcombos by selecting particular combinations of organic spacer and metalatom or ion.

Suitable refrigerants for adsorptive cooling systems as described hereininclude, but are not limited to: methyl silane, propylene, propane,propadiene, ammonia, cyclopropane, dimethyl ether, methyl acetylene,methyl phosphine, methyl nitrate, isobutene, isobutylene, 1-butene,amino methane, 1,3 butadiene, butane, trans 2-butene, trimethyl amine, cis 2-butene, 1-butene-3-one, vinyl acetylene, methane thiol, fulvene,1-butyne, neopentane, butadiyne, methylallene, cyclobutane,acetaldehyde, methanol, cycloneptane, chloro trifluoro methane,trifluoro acetonitrile, methylene fluoroide, 3,3,3-trifluoropropyne,1,1,1 trifluoroethane, nitroso-pentafluoro ethane, chloro difluoromethane, chloro pentafluoro ethane, fluoroethane, perfluordimethylamine, perfluoropropane, perfluoro ethyl amine, trifluoro methylperoxide, nitro trifluoro methane, dichloro difluoro methane, perfluoropropylene, 1,1,1,2 tetrafluoro ethane, trifluoro methyl phosphine, 1,1difluoro ethane, perfluoro 2-butyne, methyl chloride, fluoroformaldehyde, iodo trifluoro methane, trifluoromethyl sulfide, trifluoromethane sulfonyl fluoride, pentafluoro thio trifluoro methane, vinylchloride, bromo diflouoro nitroso methane, 1-nitroso heptafluoropropane, trifluoro ethoxyl silane, hexafluorodimethylamine, ethyltrifluoro silane, perfluoro cyclobutane, 3-fluoropropylene, perfluoromethyl mercaptan, 2,2, difluoro propane, nitro pentafluoro ethane,perfluoro 2-butene, trans 2-butane, 1,1,1,2,2,3 hexafluoro propane,perfluoro cyclobutene, methyl bromide, bromoacetylene, pentachlorobenzyl chloride, hexafluoro 1,3 butadiene, 2-chloro 1,1,1trifluoroethane, dichloro fluoro methane, 2-fluoro 1,3-butadiene, acetylfluoride, 1,2 dichloro 1,2 difluoro ethylene, 1-nitro heptafluoropropane, and neopentyl chloride, etc. as would be understood by onehaving ordinary skill in the art upon reading the present descriptions.

In more embodiments, the substrate may include a plurality ofmicrochannels adapted for interfacing with a metal organic framework.Moreover, according to such embodiments the metal organic framework maybe adhered to an interior and/or an exterior surface of one or more ofthe plurality of microchannels. As will be understood by one havingordinary skill in the art upon reading the present descriptions, asubstrate having a plurality of microchannels increases availablesurface area for metal organic framework binding and thus improves theoverall adsorption/desorption performance of an adsorptive coolingsystem employing a highly adsorptive structure such as the inventivemetal organic framework disposed on a substrate surface having aplurality of microchannels as described herein. Moreover, the increasedsurface area provides improved cooling capacity to such systems ascompared to typical adsorptive cooling systems employing a metal organicframework monolith positioned within a canister-type containersubstantially as described in U.S. patent application Ser. No.12/848,564 to Farmer, et al.

In still more embodiments, the metal organic framework may have anexterior surface substantially conformal to the substrate positionedadjacent thereto. As will be appreciated by one having ordinary skill inthe art upon reading the present descriptions, formation of a monolithicstructure results in the monolith taking a form substantially conformalto that of the substrate in and/or on which formation occurs.

In even more embodiments, the highly adsorptive structures describedherein may be characterized such that the substrate includes a pluralityof microchannels. As understood herein, microchannels may constitute anysuitable microstructure which increases surface area of a substrate uponwhich the microchannels are arranged. For example, in some approachesmicrochannels in the substrate may include a plurality of etches,grooves, microcapillaries, ridges, etc. as would be understood by onehaving ordinary skill in the art upon reading the present descriptions.Moreover, according to such embodiments the metal organic framework maybe adhered to an interior and/or exterior surface of the plurality ofmicrochannels.

As will be understood by one having ordinary skill in the art, adherenceto an interior and/or exterior surface of the plurality of microchannelsencompasses any binding of metal organic framework to any portion of theinterior surface of the microchannel (e.g. the interior ofmicrocapillaries 1510 as shown in FIG. 15B; a valley of a groove such asvalley 1512 of FIG. 15C, etc. as would be understood by one havingordinary skill in the art upon reading the present descriptions.)Similarly, adherence to an interior and/or exterior surface of theplurality of microchannels encompasses any binding of metal organicframework to any portion of the exterior surface includes binding to theouter surface of microcapillaries 1510 as shown in FIG. 15B, as well asbinding to a peak of a microchannel groove such as peak 1514 as shown inFIG. 15C.

Moreover, in many approaches the microchannels may improve overallsurface area and thus adsorptive cooling potential of a structureemploying a highly adsorptive structure as described herein. Suchimprovements may be further attributed at least in part to the fact thatthe microchannels provide ingress and egress paths for ambient gases,e.g. a refrigerant gas for an adsorptive cooling system. Of course, themicrochannels may provide ingress and egress paths for fluids other thangases, as would be understood by the skilled artisan reading the presentdescriptions.

Moreover still, in some approaches the metal organic framework may bebiased toward the substrate for increasing a thermal conductivitybetween the metal organic framework and the substrate. Surprisingly,improvements to thermal conductivity are achievable without the use of aconductive paste as is typically required.

The highly adsorptive structure as described herein may further includea refrigerant adsorbed to the metal organic framework in someapproaches. In preferred embodiments, the refrigerant desorbs from themetal organic framework at a temperature of less than about 90° C.

In still more embodiments, the highly adsorptive structure may have anenclosing container having an opening configured for ingress and egress,e.g. of a refrigerant. In such embodiments, the enclosing container maybe further adapted for integration with a circulation system, e.g. acirculation system adapted for circulating the refrigerant to and fromthe highly adsorptive structure.

Methods of Fabrication

As described herein, the inventive metal organic framework and substrateproduct may be fabricated according to the following process.

According to some approaches, MOFs may be prepared substantially asdisclosed in Yaghi, et al., Nature 423, 705 (2003). MOFs may befabricated in a variety of forms, including monoliths and thin films, afeature that can be advantageous for many applications.

The structure-property relationships of MOFs are largely determined bythe species of metal atom and organic spacer forming the framework.

Referring now to FIG. 17 a method 1700 is shown, according to oneembodiment. As described herein, the method 1700 may be implemented inany suitable environment, including those depicted in FIGS. 1-16, amongothers.

As shown in FIG. 17 the method 1700 initiates with operation 1702, wherea metal organic framework is formed on a substrate to produce a highlyadsorptive structure including a substrate; and a metal organicframework adhered to the substrate, where the metal organic framework isadapted for adsorbing and desorbing a refrigerant according topredetermined thermodynamic conditions.

In some approaches, the substrate includes a plurality of microchannelssuch as grooves, etches, ridges, microcapillaries, etc. as would beunderstood by one having ordinary skill in the art upon reading thepresent descriptions.

Adsorptive Cooling System Utilizing Highly Adsorptive Metal OrganicFramework Materials

The present disclosure provides a thermally controlledadsorption-desorption refrigeration and air conditioning system thatuses nanostructural materials such as metal organic frameworks as theadsorptive media. As disclosed herein, refrigerant molecules may beadsorbed on the high surface area of the nanostructural material whilethe material is at a relatively low temperature, perhaps at night.During daylight hours, when the nanostructural materials are heated bythermal energy, the refrigerant molecules may be thermally desorbed fromthe surface of the MOF, thereby creating a pressurized gas phase in thevessel that contains the MOF in some approaches. This thermallycontrolled pressurization may force the heated gaseous refrigerantthrough a condenser, followed by an expansion valve. In the condenser,heat may be removed from the refrigerant, first by circulating air orwater. Eventually, the cooled gaseous refrigerant may expandisenthalpically through a throttle valve into an evaporator.

In one embodiment, the present disclosure provides a thermallycontrolled adsorption-desorption refrigeration system. During Phase 1,incident thermal radiation may cause heating of the first bed of highspecific surface area adsorption media (Bed A), which then may causethermal desorption of the refrigerant in one approach. Refrigerantdesorption may increase the gas-phase pressure in the pores of theadsorption media, thereby forcing the gaseous refrigerant to flow out ofthe adsorption bed, through a two-stage condenser. While passing throughthe two-stage condenser, heat may be first removed from the hot gaseousrefrigerant by a stream of water that eventually flows into a hot waterheater and storage system in another approach. Then, the refrigerant maybe further cooled by chilled refrigerant leaving the evaporator aftervaporization. After passing through the two-stage condenser, the gaseousrefrigerant may undergo expansion, e.g. isenthalpic expansion, throughan expansion valve in yet another embodiment. A portion of therefrigerant may condense in the evaporator, while some of therefrigerant may be flashed, such that some of the refrigerant may changestate from a liquid to a gas while absorbing heat from the remainingliquid refrigerant, and exit the evaporator. The evaporator may absorbheat from the room or area being cooled, which may result in furthervaporization of the refrigerant. Further, in another embodiment, thecool, vaporized refrigerant may then leave the evaporator, passingthrough tubes in the shell-and-tube heat exchanger comprising the secondstage of the two-stage condenser. Once leaving the tube-side of thisheat exchanger, the cool, vaporized refrigerant may flow to the secondbed of adsorption media (Bed B), which may be maintained at a lowertemperature than the first bed in some approaches. Moreover, in someembodiments, the entire system may be allowed to cool at relatively coolambient temperatures, e.g. at night, and most of the refrigerant mayadsorb on the second adsorption bed (Bed B). During the second phase,the refrigeration cycle may be reversed, with thermal desorption fromBed B and adsorption on the cooler Bed A in some approaches.

Systems and methods in accordance with the present disclosure may beused for various purposes, including but not limited to climate control.Additionally, the present disclosure may be used for cooling homes andcommercial buildings; cooling passenger compartments in variousvehicles, including cars, trucks, commercial ships, and airplanes;cooling of high performance computing machines and electronics; coolingadvanced energy conversion and storage devices, including batteries;cooling office buildings and laboratories; cooling passengercompartments in military vehicles including trucks, tanks, armoredpersonnel carriers, naval ships, submarines, airplanes, and spacecrafts;and for cooling other structures, devices, vehicles, etc. as would beunderstood by one having ordinary skill in the art upon reading thepresent disclosure.

The system as disclosed herein may also be used in other appliances,including, but not limited to, hot water heaters, heaters, etc. andother such appliances as would be understood by one having ordinaryskill in the art upon reading the present disclosure.

Several embodiments of an adsorption-desorption refrigeration system(ADRS) constructed in accordance with the present disclosure areillustrated in FIGS. 7-14. For example, FIG. 7 illustrates oneembodiment of a thermally controlled adsorption-desorption refrigerationsystem of the present disclosure. The thermally controlledadsorption-desorption refrigeration system may be designated generallyby the reference numeral 1400. Reference numerals may be used todesignate various components, systems, units, devices which aregenerally referred to below as “item(s)” in FIGS. 7-14.

As shown in FIG. 7, item 2 may be a first bed of high specific surfacearea adsorption media, including, but not limited to, a nanostructuralfoam, MOF based media, etc. and other high specific surface areaadsorption media as would be understood by one having ordinary skill inthe art upon reading the present disclosure. In another embodiment, item4 may be a second bed with the same properties of the first bed item 2.In yet another embodiment, item 6 may be a retractable sun shade thatmay be moved to cover or uncover either beds 2 or 4 or may be positionedto uncover both beds 2 and 4 at the same time. The beds of high specificsurface area adsorption media, item 2 and item 6, may be anynanostructural material, including, but not limited to, an MOF, a solgel, a zeolite, etc. or any other nanostructural material as would beunderstood by one having ordinary skill in the art upon reading thepresent disclosure.

In one embodiment, item 2 may be any light blocking system adapted toselectively block energy from a thermal energy source, such as the sun,a heating element, waste heat, etc. or any other thermal energy sourceas would be understood by one having ordinary skill in the art uponreading the present disclosure. For example, item 2 may include, but isnot limited to, a louvered shade, a shutter shade, an electronic lightblocking system for blocking energy from a thermal energy source, etc.or any other system for blocking thermal energy as would be understoodby one having ordinary skill in the art upon reading the presentdisclosure.

As shown in FIG. 7, item 12 may be a two-way valve that connects thefirst bed 2 to the two-stage condenser 24 in one approach. Item 16 maybe a line that connects valve 12 to the condenser first stage 26 of thetwo-stage condenser in another approach. In yet another embodiment, item18 may be another line that connects valve 12 to the second stage 28 ofthe two-stage condenser. Moreover, in one approach line 30 may connectthe condenser first stage to the condenser second stage. Additionally,item 32 may be a line connecting the two-stage condenser to theexpansion valve 34 and item 36 may connect the expansion valve 34 to theevaporator 38 in another approach. In yet another embodiment, item 40may be a line connecting the evaporator 38 to the condenser secondstage.

Item 10 as shown in FIG. 7 may be a line connecting the second bed 4 toa two-way valve 14 in one approach. In another approach, item 20 may bea line that connects valve 14 to the condenser first stage 26 and item22 may be a line connecting valve 14 to the condenser second stage 28.Further, in one embodiment, item 42 may be a cold water supply,including, but not limited to, tap water entering a building, or othercold water supply as would be understood by one having ordinary skill inthe art. Moreover, in another approach, item 44 may be a line connectingthe cold water supply 42 to a pump 46 that through line 48 may connectto condenser first stage 26. Item 50 may be a line that connectscondenser first stage 26 to a hot water heater/storage module 52 in yetanother approach.

FIG. 8 illustrates one embodiment of phase 1 of the ADRS. The thermallycontrolled adsorption-desorption refrigeration system (ADRS) may bedesignated generally by the reference numeral 100. Incident thermalenergy 54 may cause heating of the first bed 2, which, in turn, maycause thermal desorption of the refrigerant stored in bed 2 in oneapproach. Refrigerant desorption may increase the gas phase pressure inthe pores of the adsorption media, and may thereby force the gaseousrefrigerant (GS) to flow-out of the first bed 2. The GS may flow throughline 8 to the two-way valve 12 and from there through line 16 to thecondenser first stage 26 of two-stage condenser 24 in another approach.In the condenser first stage 26, heat may be removed from the GS by astream of cold water supplied by cold water supply 42 and pump 46 in yetanother approach.

As shown in FIG. 8, after removing heat from the GS, the warmed watermay exit the condenser first stage by line 50 and may be stored in hotwater storage module 52 according to one approach. This hot water may beused for other purposes in whatever structure the ADRS may be used. Inanother embodiment, the cooled GS may now enter, through line 30, thecondenser second stage 28 where the GS may be further cooled by thechilled refrigerant leaving the evaporator 38 after vaporization. Afterpassing through the two-stage condenser 24, the GS may undergoisenthalpic expansion in the expansion valve 34 in yet anotherembodiment.

Additionally, in one embodiment, a portion of the GS may condense in theevaporator 38 while some of the GS may be flashed (chilled refrigerant)and may exit the evaporator 38 as shown in FIG. 8. The evaporator 38 mayabsorb heat from the room or area being cooled, which may result infurther vaporization of the GS. In another approach, the chilledvaporized GS may exit the evaporator 38 and through line 40 may enterthe condenser second stage and may proceed through the tubes of ashell-and-tube heat exchanger, which comprises the condenser secondstage 28 of the two-stage condenser 24. The GS may leave the condenserby way of line 22 and may pass through valve 14 and line 10 may bedeposited in the-adsorption media of bed 4, which is at a lowertemperature than the first bed 2 in yet another approach.

FIG. 9 illustrates one embodiment of the second phase of therefrigeration cycle. During phase two, the second bed 4 may receive thethermal energy 54 and may heat the GS, which may flow through the ADRSin the reverse order and may end up adsorbed in bed 2, which is at acooler temperature. This cycling between bed 2 and 4 may take placeseveral times during a day depending on the size of the ADRS in someapproaches.

In one embodiment, the refrigerant may include one or more materialbelonging to one or more of the following classes of materials: acidhalides, alcohols, aldehydes, amines, chlorofluorocarbons, esters,ethers, fluorocarbons, perfluorocarbons, halocarbons, halogenatedaldehydes, halogenated amines, halogenated hydrocarbons, halomethanes,hydrocarbons, hydrochlorofluorocarbons, hydrofluoroethers,hydrofluoroolefins, inorganic gases, ketones, nitrocarbon compounds,noble gases, organochlorine compounds, organofluorine compounds,organophosphorous compounds, organosilicon compounds, oxide gases,refrigerant blends and thiols.

In more embodiments, the refrigerant may include one or moreNon-Halogenated compounds. For example, some suitable Non-Halogenatedcompounds with boiling points appropriate for use as refrigerants aretabulated in Table 1.

TABLE 1 Name Formula FW BP (° C.) MP (° C.) Density (g/cc) carbondioxide CO2 44.0000 −78.6000 −56.6000 1.0310 methyl silane CH3SiH346.1200 −57.0000 −156.5000 propene or propylene CH3CHCH2 42.0800−47.4000 −185.2000 0.5193 propane CH3CH2CH3 44.1100 −42.1000 −189.70000.5831 propadiene or allene ClH2CCH2 40.0700 −34.5000 −136.0000 0.7870ammonia NH3 17.0300 −33.3500 −77.7000 0.7710 cyclopropane C3H8 42.0800−32.7000 −127.6000 0.7200 dimethyl ether CH3OCH3 46.0700 −25.0000−138.5000 methyl acertylene or propyne CH3CCH 40.0700 −23.2000 −105.50000.7062 methyl phospine CH3PH3 48.0600 −14.0000 vinyl chloride orchloroethylene CH2CHCl 62.0500 −13.4000 −153.8000 0.9106 bromo difluoronitroso methane BrF2CNO 159.9200 −12.0000 methyl nitrate CH3ONO 61.0400−12.0000 −16.0000 0.9910 isobutane (CH3)2CHCH2 58.1200 −11.7000−159.4000 0.5490 isobutylene (CH3)2CCH2 56.1100 −6.9000 −140.3000 0.59421-butene CH3CH2CHCH3 56.1200 −6.3000 −185.3000 0.5951 amino methaneCH3NH2 31.0600 −6.3000 −93.5000 0.6628 1,3 butadiene or bivinylCH2C2H2CH2 54.0900 −4.4000 −108.9000 0.6211 butane C4H10 58.1200 −0.5000−138.4000 0.6012 trans 2-butene CH3CHCHCH3 56.1200 0.9000 −105.50000.6042 trimethyl amine (CH3)3N 59.1100 2.9000 −117.2000 0.6356 cis2-butene CH3CHCHCH3 56.1200 3.7000 −138.9000 0.6213 1-butene-3-oneCH2CHCCH 52.0800 5.1000 0.7095 vinyl acetylene CH2CHCCH 52.0800 5.10000.7095 methane thiol CH3SH 48.1100 6.2000 −123.0000 0.8665 fulwene C6H678.1100 7.0000 1-butyne CH3CHCCH 54.0900 8.1000 −125.7000 0.6784neopentane (CH3)4C 72.1500 9.5000 −16.5000 0.6135 butadiyne CHCCCH50.0600 10.3000 −36.4000 0.7634 1,2 butadiene or methylallene CH2CCHCH354.0900 10.8000 −136.2000 0.6760 cyclobutane C4H8 56.1200 12.0000−50.0000 1.0457 acetaaldehyde CH3CHO 44.0500 20.8000 −121.0000 0.7834methanol CH3OH 32.0400 65.0000 −93.9000 0.7914 cycloneptane C7H1498.1900 118.5000 −12.0000 0.8098

Some suitable examples of halogenated compounds with boiling pointsappropriate for use as refrigerants are tabulated in Table 2.

TABLE 2 Name Formula FW BP (° C.) MP (° C.) Density (g/cc) chlorotrifluoro methane or Freon 13 ClCF3 104.4600 −81.1000 −181.000 trifluoroacetonitrile F3CCN 95.0300 −64.0000 methylene fluoroide CHF2 52.0200−51.6000 0.9090 3,3,3-trifluoropropyne F3CCCH 94.0400 −48.3000 1,1,1trifluoroethane CH3CF3 84.0400 −47.3000 −111.3000 nitroso-pentafluoroethane CF3CF2NO 149.0200 −42.0000 chloroo difluoro methane or Freon 22ClCHF3 86.4700 −40.8000 −146.0000 chloro pentafluoro ethane ClCF2CF3154.4700 −38.0000 −106.0000 fluoroethane CH3CH2F 48.0600 −37.7000−143.2000 0.7182 perfluorodimethyl amine (CH3) 2NF 171.0200 −37.0000perfluoropropane C3F8 188.0200 −36.0000 −183.0000 perfluoro ethyl amineCF3CF2NF2 171$$02 −35.0000 trifluoro methyl peroxide CF3OOCF3 170.0100−32.0000 nitro trifluoro methane F3CNO2 115.0100 −31.1000 dichlorodifluoro methane or Freon 12 Cl2CF2 120.9100 −29.8000 −158.0000 1.1834perfluoro propylene CF3CFCF2 150.0200 −29.4000 −156.2000 1.5830 1,1,1,2tetrafluoro ethane CH3FCF3 102.0300 −26.5000 trifluoro methyl phosphineF3COH2 102.0000 −26.5000 1,1 difluoro ethane CH3CHF2 66.0500 −24.7000−117.0000 0.9500 perfluoro 2-butyne CF3CCCF3 162.0400 −24.6000 −117.4000methyl chloride CH3Cl 50.4900 −24.2000 −97.1000 0.9159 fluoroformaldehyde FCHO 48.0000 −24.0000 iodo trifluoro methane CF3l 195.9100−22.5000 2.3608 trifluoromethyl sulfide (CF3)2S 170.0800 −22.2000trifluoro methane sulfonyl fluoride F3CSO2F 152.0700 −21.7000pentafluoro thio trifluoro methane F3C(SFS) 196.0600 −20.0000 vinylchloride or chloroethylene CH2CHCl 62.0500 −13.4000 −153.0000 0.9106bromo difluoro nitroso methane BrF2CNO 159.9200 −12.0000 1-nitrosoheptafluoro propane CF3CF2CF2NO2 199.0300 −12.0000 −150.0000 trifluoroethoxyl silane C2H5OSiF3 130.1500 −7.0000 −122.0000hexafluorodimethylamine (CF3)2NH 153.0300 −6.7000 −130.0000 ethyltrifluoro silane C2H5SiF3 114.1400 −4.4000 −105.0000 1.2270 perfluorocyclobutane C4F8 200.0300 −4.0000 −38.7000 3-fluoro propylene FCH2CHCH260.0700 −3.0000 perfluoro methyl mercaptan F3C5Cl 136.5200 −0.7000 2,2difluoro propane (CH3)2CF2 80.0800 −0.4000 −104.8000 0.9205 nitropentafluoro ethane CF3CF3NO2 165.0200 0.0000 perfluoro 2-butaneCF3CFCFCF3 200.0300 0.0000 −129.0000 1.5297 trans 2-butane CH3CHCHCH356.1200 0.9000 −105.5000 0.6042 1,1,1,2,2,3 hexafluoro propaneCH2FCF2CF3 152.0400 1.2000 perfluoro cyclobutene C4F6 162.0400 3.0000−60.0000 1.6020 methyl bromide CH38r 94.9400 3.6000 −93.6000 1.6755bromo acetylene BrCCH 104.9400 4.7000 pentachloro benzyl chlorideC6Cl5COCl 312.8000 5.0000 87.0000 hexafluoro 1,3 butadiene CF2CFCFCF2162.0400 6.0000 −132.0000 1.5530 2-chloro 1,1,1 trifluoroethane ClCH2CF3118.4900 6.9300 −105.5000 1.3890 dichloro fluoro methane or Freon 21Cl2CHF 102.9200 9.0000 −135.0000 1.4050 2-fluoro 1,3 butadieneCH2CFCFCF2 72.0800 12.0000 0.8430 acetyl fluoride CH3COF 62.0400 20.80001.0020 1,2 diclhloro 1,2 difluoro ethylene CFClCFCl 132.9200 21.1000−130.5000 1.4950 1-nitro heptafluoro propane CF3CF2CF2NO2 215.030025.0000 neopentyl chloride (CH3)3CCH2Cl 106.6 84.3000 −20.0000 0.8660

FIG. 10 illustrates one embodiment of the ADRS during the night time.The retractable sun shade 6 may be positioned to uncover both beds 2 and4 and both beds may radiate heat 56. Most of the refrigerant may beadsorbed in bed 4 in some approaches.

FIG. 11 illustrates one embodiment of a scanning electron microscopeview of a section of MOF showing pores in the MOF. The presentdisclosure may utilize MOF nanotechnology for dramatic enhancements inthe active surface area of the adsorptive media. MOF nanotechnology,including, but not limited to, the advanced MOF technology developed bythe Lawrence Livermore National Laboratory (LLNL), may be used in one ormore embodiments of this invention. For example, carbon based MOFs maybe made with surface areas ranging from 600 to 3125 square meters pergram. Compare with the best activated carbons made from coconut hullsand similar materials, which have specific surface areas of 100 to 1500square meters per gram. Since sorption capacity is proportional tospecific surface area, with the adsorption of approximately 1014molecules per square meter in some cases, the higher surface areaattainable with metal organic frameworks may reduce the required mass ofthe adsorption bed, thereby leading to a refrigeration or airconditioning system of lower weight and smaller size. In addition to theuse of metal organic frameworks, other types of MOFs may be usedincluding, but not limited to, a wide variety of MOFs made of silica andmetal oxides, etc. and other MOFs as would be understood by one havingordinary skill in the art upon reading the present disclosure.

FIG. 11 illustrates one embodiment of the predicted Langmuir adsorptionisotherm for a better refrigerant and adsorption-medium combination atvarious temperature levels. These predictions were based upon the freeenergy of adsorption and pre-exponential for calculation of the Langmuirparameter summarized below. In one approach, a possible refrigerationcycle is shown as an overlay on the isotherm. The legend givespredictions for various temperature levels (° F.) according to such anapproach.

As shown in FIG. 11, temperature changes induced by thermal heating maybe sufficient to cause enough change in surface coverage and gas-phasepressure to drive a practical refrigeration cycle. For a metal organicframework with a demonstrated active surface area of 3,125 square metersper gram, and assuming a monolayer coverage of isobutane, a mass loadingof approximately 0.6 grams of isobutene per gram of MOF may beestimated. By using materials with even higher surface areas, loadingsof 1 gram per gram or better may be possible in some embodiments.

In another embodiment, the fractional coverage of active sites on thesurface of the MOF by adsorbed refrigerant may then be calculated fromthe Langmuir parameter and the gas-phase chemical activity of thespecies being adsorbed. The chemical activity is proportional togas-phase above the surface where adsorption is occurring. Langmuiradsorption isotherms have been predicted for various compounds,including isobutane on zeolites, as a function of pressure andtemperature. In the case of isobutane adsorbed on zeolite, predictionswere based upon Langmuir parameters determined from the regressionanalysis of published data.

In one embodiment, where isobutene may be adsorbed on zeolite,temperature changes induced by thermal energy may be insufficient tocause enough change in surface coverage and gas-phase pressure to drivea practical refrigeration cycle. Similar predictions have been made withoptimized combinations of refrigerant and adsorption media (optimumspecified in terms of predicted Langmuir parameter). Temperature changesinduced by thermal heating may be sufficient to cause enough change insurface coverage and gas-phase pressure to drive a practicalrefrigeration cycle in some approaches.

Adsorption of refrigerant on the surface of the MOF (or other adsorptionmedia) may obey the Langmuir adsorption isotherm. The Langmuir parameterfor species K_(i) is defined by the Gibbs free energy of adsorption, theuniversal gas constant, and the absolute temperature:

$\begin{matrix}{K_{i} = {\exp \left( \frac{{- \Delta}\; G_{i}}{RT} \right)}} & {{Equation}\mspace{14mu} 1}\end{matrix}$

In one embodiment, the fractional coverage of active sites on thesurface of the MOF by adsorbed refrigerant may then be calculated fromthe Langmuir parameter and the gas-phase chemical activity of thespecies being adsorbed (a). The chemical activity (a) is proportional togas-phase above the surface where adsorption is occurring.

$\begin{matrix}{{\frac{\theta}{1 - \theta} = {a\; {\exp \left( \frac{{- \Delta}\; G_{ADS}}{RT} \right)}}}{\theta = \frac{a\; {\exp \left( \frac{{- \Delta}\; G_{ADS}}{RT} \right)}}{{a\; {\exp \left( \frac{{- \Delta}\; G_{ADS}}{RT} \right)}} + 1}}} & {{Equation}\mspace{14mu} 2}\end{matrix}$

In other embodiments involving multi-component refrigerants,refrigerants may compete for available active sites, in accordance withthe following modified adsorption isotherm.

$\begin{matrix}{\theta_{i} = \frac{K_{i}a_{i}}{1 + {K_{i}a_{i}} + {K_{l}a_{l}}}} & {{Equation}\mspace{14mu} 3}\end{matrix}$

FIG. 12 illustrates one embodiment of a possible refrigeration cycle.The path from F to A may represent condenser operation between 175° F.and 140° F., removing superheat and the latent heat of vaporization fromthe refrigerant in one approach. In another embodiment, the path from Ato B may represent the expansion of refrigerant, with partialcondensation in the evaporator, which is assumed in this example to beoperating at 10° F. Moreover, the adsorption bed may operate along thepath between points E and F in yet another approach. These arecalculations that may not account for the transient nature of the systemin some embodiments.

FIG. 13 illustrates another embodiment of a thermally controlledadsorption-desorption refrigeration system (ADRS) constructed inaccordance with the present disclosure. As shown in FIG. 13, thethermally controlled adsorption-desorption refrigeration system may bedesignated generally by the reference numeral 1300. Reference numeralsare used to designate various components, systems, units, and devices,which are generally identified as “item(s)” in FIGS. 7-14.

In one embodiment, item 1402 may be a bed(s) of high specific surfacearea adsorption media, including, but not limited to, a nanostructuralfoam, an MOF based media 1404, etc. or other high specific surface areaadsorption media as would be understood by one having ordinary skill inthe art. The bed(s) 1402 may be of high specific surface area adsorptionmedia 1404 in one approach. Item 1404 may be any nanostructural materialincluding, but not limited to, an MOF, a sol gel, a zeolite, etc. or anyother nanostructural material as would be understood by one havingordinary skill in the art. Item 1406 may be a refrigerant.

Additionally, in one embodiment, item 1408 may be a cooling unit. Item1408 may include a two-stage condenser and an expansion valve in oneapproach. Further, in one embodiment, item 1410 may be a circulationsystem for circulating the refrigerant from the bed or beds ofadsorption media to the cooling unit to provide cooling from energy fromthe sun and to return the refrigerant from the cooling unit to the bedor beds of adsorption media.

The U.S. Department of Energy (DOE) estimates the total primary energyconsumption for commercial buildings was 10.72 quadrillion BTU (quads)in 1983, compared with 14.74 quads for the residential sector. Accordingto the DOE Building Technologies Program, 40-60% of the energy used inU.S. commercial (and residential) buildings is for HVAC, creatingmassive potential for energy savings with a system that could cutcooling energy use by at least 30-60%. Initial vertical segments in thecommercial building market may include, but are not limited to,government and commercial office buildings; government facilities suchas prisons, military bases, and schools; hotels and resorts; farming,wineries and other rural facilities; general light industrial offices,printers and clothing makers, etc.

The present disclosure relates to a thermally controlled MOF-basedadsorption cooling system. In one embodiment of this cooling system,thermal energy may be focused by thermal collectors onto on bed, whichmay contain an ultra high surface area MOF. Heating may cause thermaldesorption of a refrigerant previously adsorbed into the MOF's pores. Inanother approach, refrigerant desorption may increase the gas-phasepressure in the pores, and may thereby force the gaseous refrigerant toflow out of the irradiated bed and through a two-stage condenser. In thecondenser, heat may be first removed from the hot gaseous refrigerant bya stream of water that eventually flows into a hot water heater andstorage system. The refrigerant may then be further cooled by chilledrefrigerant leaving the evaporator after vaporization.

After passing through the two-stage condenser, the gaseous refrigerantmay undergo expansion through an expansion valve in one embodiment. Aportion of the refrigerant may condense in the evaporator, while some ofthe refrigerant may be flashed and may exit the evaporator. Theevaporator may absorb heat from the area being cooled, which may resultin further vaporization of the refrigerant. In another approach, thecool, vaporized refrigerant may leaves the evaporator and may passthrough tubes in the shell-and-tube heat exchanger comprising the secondstage of the two-stage condenser. After leaving the tube side of thisheat exchanger, the cool, vaporized refrigerant may flow back to the bedof MOF.

In one embodiment, most of the refrigerant may adsorb on the bed duringthe first cycle. When the refrigeration cycle is reversed, therefrigerant may thermally desorb from the bed in some approaches. As thecycling rate increases, the quantity of adsorption media, the systemsize, and the associated cost may become smaller.

As disclosed herein, some examples of the underlying features andadvantages of the present disclosure may include, but are not limitedto: (1) thermally controlled thermal desorption of a refrigerant from asuitable high-surface area media may be used instead of mechanicalcompressors as the basis of an efficient refrigeration cycle, therebyreducing the need for electrical power from grids for cooling homes andoffices; (2) sorption capacity is proportional to specific surface area,with the adsorption of approximately 1014 molecules per square meter insome embodiments; (2) the higher surface area attainable with metalorganic frameworks may reduce the required mass of the adsorption bed,thereby enabling the construction of an adsorption-type air conditioningsystem of lower weight and smaller size relative to those relying oncommercially available sorbent materials; (3) metal organic frameworkmay be fabricated as monolithic flat sheets for optimal heat and masstransfer in the adsorption bed; (4) metal organic frameworks may bereadily modified to tune the thermodynamics of adsorption, providingflexibility in the selection of refrigerants-including non-CFCs- and inoperating temperatures; (5) injection-molded silica MOF has the highestheat transfer resistance of any known engineered material and may beused to control heat leakage in the system, thereby increasing overallefficiency; (6) by eliminating moving parts, longer service life, lowermaintenance costs and lower levels of noise may be achieved, etc. aswould be understood by one having ordinary skill in the art upon readingthe present disclosure.

MOFs are among the most versatile materials available owing to theirwide variety of exceptional properties. For example, MOFs are known toexhibit the lowest thermal conductivities (0.017−0.021 W/m·K), soundvelocities (<500 m/s), and refractive indexes (1.001−1.15) of any bulksolid material. Most of the properties of bulk MOFs may also beexhibited in other forms of the material, including, but not limited tothin sheets, films, etc. or other material as would be understood byunderstood by one having ordinary skill in the art upon reading thepresent disclosure, which may be important for integration of thesematerials into devices. As a result, MOFs have been developed for avariety of applications, including, but not limited to, catalysis,sensing, thermal insulation, waste management, molds for molten metals,optics, capacitors, energetic composites, imaging devices, cosmic dustcollection, high-energy-density physics applications, etc.

LLNL is recognized as a world leader in MOF research, holding severalpatents in the technology dating back to the mid-1990s. Organic andmetal organic frameworks were both invented at LLNL, and much of thetechnology resulting from that research has been licensed for varioustechnologies, including capacitors and desalination. The process used tosynthesize high-surface-area metal organic framework adsorbents was alsodeveloped at the Laboratory, where the materials are currently used asadsorbents for hydrogen in low-pressure storage tanks. In addition, therapid supercritical extraction (RSCE) process that may be used tofabricate the insulating MOF parts in accordance to one embodiment wasdeveloped and patented by LLNL. The RSCE process—similar to injectionmolding, a common process used to manufacture some plastics—may offer anumber of advantages over conventional supercritical drying, includingsimpler and less costly hardware, monolithic gels that do not have to bepre-formed, and an overall much faster process—the entire process formaking monolithic parts may be accomplished in just a few hours insteadof the several days required by conventional supercritical drying. TheRSCE process may be extremely valuable in the fabrication of conformablemonolithic for the proposed cooling system's insulation in someapproaches.

Many conventional solar concentrators rely on parabolic mirrors to heatpipes located at the focal points of the mirrors. In the case ofadsorptive refrigeration and cooling systems, this may dictate that theadsorption media be placed in a cylindrical envelope for the mostefficient heating. Alternatively, large inexpensive Fresnel optics, nowavailable, may be used for solar collection from the solar-side ofplanar panels, providing designers with some engineering advantage. Inone embodiment, commercially available molded acrylic lenses orreflective concentrators may be used.

Metal organic framework (MOF) is a unique porous solid with networkstructures consisting of interconnected carbon particles and, as aresult, these materials exhibit many interesting properties, such ashigh surface-to-volume ratios, continuous porosities and high electricalconductivity. Lawrence Livermore National Laboratory has developed asynthetic approach to fabricate MOFs with BET surface areas of over3,000 m²/g. These surface area values are comparable to those of thehighest surface area activated carbons. In one embodiment, the syntheticstrategy may involve the thermal activation of a MOF material withstructural features (particles and pores) on the micrometer scale. Thisapproach may not only provide access to high surface areas in MOFmaterials but may also afford monolithic materials with bimodal porosity(macro- and micropores).

An important criterion for effective physisorption is a high surfacearea that exposes a large number of sorption sites to ad-atom orad-molecule interaction. Moreover, these sites need to have potentialwells that are sufficiently deeper than kT if physisorbents are tooperate at reasonable engineering temperatures. Porous carbon materialsare promising candidates for the physisorption of refrigerant gases duetheir lightweight frameworks and high accessible surface areas. Highsurface area carbons have been studied extensively for low pressurestorage of transportation fuels, such as hydrogen and methane. In oneembodiment, appreciable amounts of methane may be adsorbed onconventional high surface area activated carbons at 298 K and 3.5 MPa.More specifically, the loading of CH₄ on such activated carbons may beapproximately 17 weight percent or 0.17 grams of methane per gram ofsolid carbon.

Metal organic frameworks (MOFs) are a unique class of porous carbonsthat possess ultrafine cell sizes, continuous porosities and low massdensities. These properties arise from the MOF microstructure, athree-dimensional network of interconnected primary carbon particleswith diameters that can range from a few nanometers to several microns.In one embodiment, mechanically robust MOF monoliths may besynthetically fabricated with BET surface areas in excess of 3,000 m²/gof metal organic framework, substantially greater than that achievablewith the best activated carbons. These surface area values are thehighest reported for MOFs and exceed the accessible surface area in mostcommercially available activated carbons.

In addition to extremely large specific surface areas, MOFs exhibit anumber of other desirable qualities for the adsorption of refrigerantgases. For example, the porosity in these MOFs is bimodal, consisting ofa large population of micropores (0.7 to 1.2 nanometers in diameter)connected by a continuous macroporous network. Hierarchically porouscarbons of this type are superior to carbons with unimodal porosity(i.e. activated carbons) in terms of diffusion efficiency and surfacearea. In one embodiment, the surface chemistry of the MOF may be readilymodified to tune the interaction (binding energy) between therefrigerant gas and the adsorbent. This aspect may be particularlyimportant for controlling desorption of refrigerant from the MOF duringthermal heating.

MOFs do not require the specialized drying processes including, but notlimited to supercritical extraction, that are typically employed in thesynthesis of other MOF materials, minimizing both the fabrication timeand cost associated with these materials. In yet another embodiment, theMOFs may be fabricated in a variety of forms, including, but not limitedto, conformable monoliths, a feature that may be advantageous for thisapplication. The flexibility associated with the design of thesematerials may not only facilitate the optimization ofadsorbate-adsorbent interactions, but also maximize the gravimetric andvolumetric capacities of these MOF materials in some approaches.

In one embodiment, the system may use a two-stage condenser to cool andcondense the desorbed refrigerant. The first stage may use an externalwater stream, resulting in a hot water stream for other uses. The secondstage may be chilled by the return line of evaporated and expandedrefrigerant.

In one embodiment, the evaporator may be a two-phase boiler with bothliquid and gaseous refrigerant. Liquid may continuously evaporate asheat is absorbed from the building primary heat exchanger. Additionally,in some approaches, the primary heat exchanger may be of anyconventional design, which will allow easy retrofit of the proposedsystem into new or existing construction.

Silica MOFs are a special class of open-cell foams derived from highlycross-linked gels that are dried using special techniques (supercriticalextraction) to preserve the tenuous solid network. These materials haveultrafine cell and pore sizes (<1,000 Å), continuous porosity, highsurface area density, and a microstructure composed of interconnectedcolloidal-like particles or polymeric chains with characteristicdiameters of 100 Å. This microstructure is responsible for the unusualoptical, acoustical, thermal, and mechanical properties of silica MOFs.In fact, silica MOFs have the lowest thermal conductivity (0.017−0.021W/m·K) of any solid material and, as a result, have been commerciallydeveloped for thermal insulation applications. In one embodiment, silicaaerogels may be used as insulators for the proposed AC system. The rapidsupercritical extraction process used to fabricate these materials isscalable and may be used for high-throughput production of insulatingparts in some approaches.

In one embodiment, the components as disclosed herein may be designed tobe compatible with existing building ventilation systems.

FIG. 14 illustrates one embodiment of a thermally controlledadsorption-desorption refrigeration system (ADRS) constructed inaccordance with the present disclosure. As shown in FIG. 14, thethermally controlled adsorption-desorption refrigeration system may bedesignated generally by the reference numeral 1400. Reference numeralsmay be used to designate various components, systems, units, anddevices, which are generally identified as “item(s)” in FIGS. 7-14.

In one embodiment, item 1402A may be a first bed of high specificsurface area adsorption media, including, but not limited to,nanostructural foam, MOF based media, etc. or other high specificsurface area adsorption media as would be understood by one havingordinary skill in the art upon reading the present disclosure. Inanother embodiment, item 4 may be a second bed with the same propertiesof the first bed item 1402A. In yet another embodiment, item 1402B maybe a retractable sun shade that may be moved to cover or uncover eitherbeds 1402A or 4 or may be positioned to uncover both beds 1402A and 4 atthe same time. Moreover, in another embodiment, the beds of highspecific surface area adsorption media, item 1402A and item 1402B, maybe any nanostructural material including, but not limited to, an MOF, asol gel, a zeolite, etc. or any other nanostructural material as wouldbe understood by one having ordinary skill in the art.

In one embodiment, item 1412 may be any blocking system adapted toselectively block thermal energy including, but not limited to, alouvered shade, a shutter shade, an electronic blocking system forblocking energy from the sun, etc. or any other system for blockingthermal energy as would be understood by one having ordinary skill inthe art.

As shown in FIG. 14, refrigerant desorption may increase the gas phasepressure in the pores of the adsorption media, thereby forcing thegaseous refrigerant (CR) to flow-out of the first bed 1402A in oneapproach. In another approach, the GS may flow to the condenser 1408.After passing through the two-stage condenser, the GS may undergoisenthalpic expansion in the expansion valve in yet another embodiment.Additionally, in another embodiment, a portion of the GS may condense inthe evaporator while some of the GS may be flashed (chilled refrigerant)and exit the evaporator. The evaporator may absorb heat from the room orarea being cooled, which may result in further vaporization of the GS.

Additionally, in one embodiment, the chilled valorized GS may exit theevaporator and, through a line, may enter the condenser second stage andproceed through the tubes of a shell-and-tube heat exchanger whichcomprises the condenser second stage of the two-stage condenser. Inanother approach, the GS may then leave the condenser by way of a lineand pass through a valve and deposited in the-adsorption media of bed1402B, which is at a lower temperature than the first bed 1402A.

In other approaches, an adsorptive cooling system may take alternativeembodiments. For example, in one embodiment an adsorptive cooling systemincludes a first highly adsorptive structure positioned to receivethermal energy from a thermal energy source and a second highlyadsorptive structure positioned to receive thermal energy from thethermal energy source (such as bed 1402A and/or 1402B of FIG. 14).

In more approaches, the adsorptive cooling system may further include asecond highly adsorptive structure comprising a second substrate; asecond metal organic framework adhered to the second substrate, wherethe second metal organic framework is adapted for adsorbing anddesorbing a refrigerant according to predetermined thermodynamicconditions, a cooling unit; and a circulation system adapted forcirculating a refrigerant from at least one of the first highlyadsorptive structure and the second highly adsorptive structure to thecooling unit to provide cooling from the thermal energy source and toreturn the refrigerant from the cooling unit to at least one of thefirst highly adsorptive structure and the second highly adsorptivestructure.

In still more approaches, an adsorptive cooling system includes a firsthighly adsorptive structure positioned to receive thermal energy from athermal energy source. Moreover, as described above the first highlyadsorptive structure may include a first substrate and a first metalorganic framework adhered to the first substrate. Similarly, in someapproaches a second highly adsorptive structure positioned to receivethermal energy from the thermal energy source includes a secondsubstrate; a second metal organic framework adhered to the secondsubstrate, a cooling unit; and a circulation system adapted forcirculating the refrigerant from at least one of the first highlyadsorptive structure and the second highly adsorptive structure to thecooling unit to provide cooling from the thermal energy source and toreturn the refrigerant from the cooling unit to at least one of thefirst highly adsorptive structure and the second highly adsorptivestructure, where the first and second metal organic frameworks are eachadapted for adsorbing and desorbing a refrigerant according topredetermined thermodynamic conditions.

In some approaches, the first and/or second substrate may include aplurality of microchannels, where each of the first metal organicframework and the second metal organic framework are adhered to aninterior and/or exterior surface of the plurality of microchannels.Moreover, the microchannels may be defined by grooves in a surface ofthe substrate nearest the metal organic framework, surfaces of aplurality of microcapillaries arranged along a surface of the substratenearest the metal organic framework, ridges in a surface of thesubstrate nearest the metal organic framework, etc. as would beunderstood by one having ordinary skill in the art upon reading thepresent descriptions.

Of course, the plurality of microchannels may permit adherence of themetal organic framework in any location as would be understood by onehaving ordinary skill in the art upon reading the present descriptions.In particular, in several approaches the metal organic framework may beadhered to one or more of the interior surface of a microcapillary, theexterior surface of a microcapillary, the exterior surface of a ridgeand/or valley of a plurality of microchannels, any combination thereof,and etc. as would be understood by one having ordinary skill in the artupon reading the present descriptions.

Moreover still, in preferred embodiments the microchannels provideimproved ingress and egress to and from the metal organic framework fora binding agent such as a refrigerant, especially relative to atraditional cylindrical canister disposition for a highly adsorptivestructure such as a metal organic framework. Notably, as understoodherein grooves may include in inner and/or outer surfaces of thesubstrate.

Several exemplary embodiment of a substrate having a plurality ofmicrochannels is depicted in FIGS. 15A-15C, with several correspondingmicrochannel arrangements shown in FIGS. 16A-16D. In particular, asshown in FIG. 15A, an adsorptive cooling system may include a one ormore substrates 1502 such as corrugated substrate 1502. Moreover, suchcorrugated substrates may be arranged as shown in FIG. 15A to formintermittent diamond-like structures to maximize surface area of anoverall absorptive structure. Furthermore, the corrugated substrate maybe further defined by a plurality of peaks 1506 and valleys 1504, insome approaches.

Moreover, as shown particularly in FIGS. 15B and 15C, the substrate mayfurther include a plurality of microchannels such as shown in zoomedregion 1508. In particular, in some embodiments the substrate 1502 mayinclude a plurality of microcapillaries 1510 as shown substantially inFIG. 15B. Additionally and/or alternatively the substrate 1502 mayinclude a plurality of grooves such as shown in FIG. 15C, such groovesbeing defined by a plurality of peaks 1514 and valleys 1512, in someapproaches. Of course, as would be understood by one having ordinaryskill in the art upon reading the present descriptions, otherarrangements of microchannels may be employed, including nominalvariations to the structural arrangements shown in FIGS. 15B-15C, invarious approaches.

Moreover still, the microchannels may be arranged according to anysuitable configuration such as shown in FIGS. 16A-16D, in someapproaches. Particularly, the microchannels may be arranged in aconcentric patterns of channels such as to substantially form parallelchannels in the shape of a U, as shown in FIG. 16A, a straight line asshown in FIG. 16B, an “s” curve as shown in FIG. 16C, and a zig-zagpattern as shown in FIG. 16D, in various embodiments. Of course, aswould be understood by one having ordinary skill in the art upon readingthe present descriptions, any suitable arrangement may be employed andthose arrangements depicted in FIGS. 16A-16D are made merely forillustrative purposes.

In particularly preferred approaches, an adsorptive cooling system asdisclosed herein further characterized by a 7 kilowatt (kW) coolingcapacity and/or an electrical to cooling energy coefficient ofperformance (COP) greater than 3.8.

Different embodiments of Applicant's invention may include orincorporate one or more of the following features:

Solar driven adsorption-based refrigeration cycle—This inventiondirectly converts solar heat to the work of compression necessary todrive the adsorption-based refrigeration system. The outer surface ofthe pressure envelope surrounding the adsorption bed would be coated tomaximize the absorption of solar radiation. Solar concentration may alsobe used, exploiting concave mirrors and large-format Fresnel lenses.

High surface area MOF adsorption beds—This invention exploit's LLNL'sMOF nanotechnology for dramatic enhancements in the active surface areaof the adsorptive media. LLNL's advanced MOF technology will be used inone embodiment of this invention. For example, carbon based MOFs can bemade with surface areas ranging from 600 to 3125 square meters per gram.In contrast, the best activated carbons, made from coconut hulls andsimilar materials, have specific surface areas of 100 to 1500 squaremeters per gram. Since sorption capacity is proportional to specificsurface area, with the adsorption of approximately 1014 molecules persquare meter in some cases, the higher surface area attainable withmetal organic frameworks can reduce the required mass of the adsorptionbed, thereby leading to a refrigeration or air conditioning system oflower weight and smaller size. In addition to the use of metal organicframeworks, other types of MOFs can also be used, including a widevariety of MOFs made of silica and metal oxides.

Adsorption bed in form of monolithic sheets—Sheets of monolithic metalorganic frameworks provide not only ultra high surface area, but alsothe ability to construct flat sheets with optimal heat and mass transfercharacteristics. These monolithic sheets of MOF can be bonded to theinner surfaces of the pressure envelope surrounding the adsorption bed.

Ability to use non-CFC refrigerants—It is now widely accepted that CFC,HFC, and HCFC refrigerants, as well as other halogenated molecules, posea serious threat to the Earth's ozone layer. The use of non-halogenatedrefrigerants is therefore desirable from an environmental perspective.This invention is capable of using a wide variety of both halogenated,as well as more environmentally benign non-halogenated refrigerants.

Exceptional thermal insulation—In one embodiment, the invention usesinjection-molded silica MOF for thermal insulation. This insulation hasthe highest heat transfer resistance of any known engineering material,and will therefore help control heat leakage in the refrigeration andair conditioning system, therefore increasing the overall efficiency ofthe system.

No moving parts—The invention relies on the solid adsorption bed forcompression, and has no moving parts, Therefore; the service life ofrefrigeration and air conditioning cycles based upon this technology areexpected to have unlimited service life, and virtually eliminate wearout associated with moving parts. No lubricants are required. Theelimination of moving parts will dramatically reduce the noise from thecooling system, which will be especially desirable in urban settings.

Hermetically sealed system—By eliminating the need for moving parts andelectrical feed-through, a hermetically sealed pressure envelope thatcontains the refrigerant can be used. This will minimize the probabilityof refrigerant leakage from the system, and will therefore eliminate theneed for periodic charging of the system with makeup refrigerant.

Enhanced solar collection—The world's largest Fresnel optics, originallydeveloped for the National Ignition Facility, can be used to enhancesolar concentration and increase the upper operating temperature of theadsorption bed during thermal desorption, thereby achieving highercompression and greater efficiency. Depending upon the convention used,this feature will increase the COP (coefficient of performance), theSEER (seasonal energy efficiency rating), or the EER (energy efficiencyrating) of the system.

Flexible heating options—Sufficient flexibility to use fossil fuel orelectricity for auxiliary heating. This system can also be operated fromother heat sources, including waste heat from automotive engines,industrial plants, and nuclear power plants. This novel refrigerationsystem is therefore suitable for high latitude, cold climates and cloudydays.

Integration with hot water heater—The system will have an integrated hotwater heater or heaters.

Benefits

Applicant's invention benefits including the following:

Compared to traditional cooling systems, this technology has severaladvantages. For example, a carbon-based actuator material islight-weight, inexpensive and environmentally friendly (e.g., lead isnot a required material). Also, the technology is scalable, that is,large monolithic actuators can be envisioned, e.g., greater than about 1mm³, greater than about 1 cm³, greater than about 10 cm³, etc. Moreover,such larger structures may be formed of one contiguously-formedstructure or several smaller structures coupled together. Moreoverstill, the material can be formed in many different shapes, for exampleas depicted in FIGS. 2-5.

Further advantages include the technology is safe: a low-voltage drivingsignal may be used in some embodiments. Further, the material in someembodiments is thermally stable up to at least 1000 degrees C. (in aninert atmosphere), and potentially up to about 1500 degrees C. and thusmay allow for high temperature applications depending on the thermalstability of the electrolyte. In addition, the material in someembodiments is equally well-suited for hydrogen storage, supercapacitorand electro-catalysis applications (fuel cells).

1. Solar powered with flexibility for alternative heating options

2. Ultra-high surface area adsorption media, with substantially higherrefrigerant adsorption capacity per mass of adsorption bed, reducingsize and making installation easier

3. No moving parts, extreme reliability, and silent operation

4. Hermetically sealed refrigeration loops, preventing leakage,eliminating need for lubricants and recharging, and enabling recyclingof refrigerant

5. Monolithic sheets of adsorption media for superior heat and masstransfer

6. World's best-known insulation better control of heat flow andimproved system efficiency

7. Higher thermal desorption temperature and compression for betterefficiency

8. Integration of other household appliances, such as hot water heater.

Additional details of Applicant's invention are described andillustrated in U.S. Provisional Patent Application No. 61/1256,243entitled “Solar-Powered Adsorptive Refrigeration Cycle withNanostructural Foam & MOF Based Media” filed Oct. 29, 2009 by Farmer,which is hereby incorporated in its entirety by reference for allpurposes.

While the invention may be susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and have been described in detail herein.However, it should be understood that the invention is not intended tobe limited to the particular forms disclosed. Rather, the invention isto cover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the followingappended claims.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example only, and notlimitation. Thus, the breadth and scope of a preferred embodiment shouldnot be limited by any of the above-described exemplary embodiments, butshould be defined only in accordance with the following claims and theirequivalents.

What is claimed is:
 1. A product comprising a highly adsorptivestructure, the highly adsorptive structure comprising: a substrate; anda metal-organic framework (MOF) comprising a plurality of metal atomscoordinated to a plurality of organic spacer molecules; wherein the MOFis coupled to at least one surface of the substrate, wherein the MOF isadapted for adsorbing and desorbing a refrigerant under predeterminedthermodynamic conditions, the refrigerant being selected from the groupconsisting of: acid halides, alcohols, aldehydes, amines,chlorofluorocarbons, esters, ethers, fluorocarbons, perfluorocarbons,halocarbons, halogenated aldehydes, halogenated amines, halogenatedhydrocarbons, halomethanes, hydrocarbons, hydrochlorofluorocarbons,hydrofluoroethers, hydrofluoroolefins, inorganic gases, ketones,nitrocarbon compounds, noble gases, organochlorine compounds,organofluorine compounds, organophosphorous compounds, organosiliconcompounds, oxide gases, refrigerant blends and thiols.
 2. The product asrecited in claim 1, wherein the predetermined thermodynamic conditionsare based on an identity of each of: the plurality of metal atoms, theplurality of organic spacer molecules, and the refrigerant.
 3. Theproduct as recited in claim 1, wherein the MOF is characterized by asurface area of at least about 5000 m²/g.
 4. The product as recited inclaim 1, wherein the MOF is characterized by a pore structure, whereinthe pore structure is determined based on an identity of each of: theplurality of metal atoms and the plurality of organic spacer molecules.5. The product as recited in claim 1, wherein the refrigerant isselected from the group consisting of: methyl silane, propylene,propane, propadiene, ammonia, cyclopropane, dimethyl ether, methylacetylene, methyl phosphine, bromo difluoro nitroso methane, methylnitrate, isobutene, isobutylene, 1-butene, amino methane, 1,3 butadiene,butane, trans 2-butene, trimethyl amine, cis 2-butene, 1-butene-3-one,vinyl acetylene, methane thiol, fulvene, 1-butyne, neopentane,butadiyne, methylallene, cyclobutane, acetaldehyde, methanol,cycloneptane, chloro trifluoro methane, trifluoro acetonitrile,methylene fluoroide, 3,3,3-trifluoropropyne, 1,1,1 trifluoroethane,nitroso-pentafluoro ethane, chloro difluoro methane, chloro pentafluoroethane, fluoroethane, perfluordimethyl amine, perfluoropropane,perfluoro ethyl amine, trifluoro methyl peroxide, nitro trifluoromethane, dichloro difluoro methane, perfluoro propylene, 1,1,1,2tetrafluoro ethane, trifluoro methyl phosphine, 1,1 difluoro ethane,perfluoro 2-butyne, methyl chloride, fluoro formaldehyde, iodo trifluoromethane, trifluoromethyl sulfide, trifluoro methane sulfonyl fluoride,pentafluoro thio trifluoro methane, vinyl chloride, bromo diflouoronitroso methane, 1-nitroso heptafluoro propane, trifluoro ethoxylsilane, hexafluorodimethylamine, ethyl trifluoro silane, perfluorocyclobutane, 3-fluoropropylene, perfluoro methyl mercaptan, 2,2,difluoro propane, nitro pentafluoro ethane, perfluoro 2-butene, trans2-butane, 1,1,1,2,2,3 hexafluoro propane, perfluoro cyclobutene, methylbromide, bromoacetylene, pentachloro benzyl chloride, hexafluoro 1,3butadiene, 2-chloro 1,1,1 trifluoroethane, dichloro fluoro methane,2-fluoro 1,3-butadiene, acetyl fluoride, 1,2 dichloro 1,2 difluoroethylene, 1-nitro heptafluoro propane, and neopentyl chloride.
 6. Theproduct as recited in claim 1, wherein the substrate comprises aplurality of microchannels, wherein the MOF is coupled to an interiorand/or exterior surface of the plurality of microchannels.
 7. Theproduct as recited in claim 6, wherein the microchannels are defined bygrooves in a surface of the substrate nearest the MOF.
 8. The product asrecited in claim 7, wherein the substrate having the grooves iscorrugated.
 9. The product as recited in claim 8 wherein the groovesprovide ingress and egress paths for the refrigerant.
 10. The product asrecited in claim 7, wherein the microchannels are defined by inner orouter surfaces of a plurality of microcapillaries of the substrate. 11.The product as recited in claim 10, wherein the microcapillaries provideingress and egress paths for the refrigerant.
 12. The product as recitedin claim 1, wherein the refrigerant is adsorbed to the MOF, wherein therefrigerant desorbs from the MOF at a temperature of less than 90° C.13. The highly adsorptive structure as recited in claim 1, furthercomprising a container enclosing the MOF coupled to the substrate, thecontainer having an opening configured for ingress and egress of therefrigerant.
 14. The product as recited in claim 13, further comprisinga circulation system adapted for facilitating circulation of therefrigerant to and from the MOF coupled to the substrate.
 15. Anadsorptive cooling system comprising: a first highly adsorptivestructure as recited in claim 1 and positioned to receive thermal energyfrom a thermal energy source; a second highly adsorptive structurepositioned to receive thermal energy from the thermal energy source, thesecond highly adsorptive structure comprising: a second substrate; and asecond MOF adhered to the second substrate, wherein the second MOF isadapted for adsorbing and desorbing a refrigerant under predeterminedthermodynamic conditions, and a cooling unit; and a circulation systemadapted for circulating the refrigerant from at least one of the firsthighly adsorptive structure and the second highly adsorptive structureto the cooling unit to provide cooling from the thermal energy sourceand to return the refrigerant from the cooling unit to at least one ofthe first highly adsorptive structure and the second highly adsorptivestructure.
 16. An adsorptive cooling system comprising: a first highlyadsorptive structure positioned to receive thermal energy from a thermalenergy source, the first highly adsorptive structure comprising: a firstsubstrate; and a first metal-organic framework (MOF) coupled to thefirst substrate and adapted for adsorbing and desorbing a refrigerantunder predetermined thermodynamic conditions, a second highly adsorptivestructure positioned to receive thermal energy from the thermal energysource, the second highly adsorptive structure comprising: a secondsubstrate; and a second MOF coupled to the second substrate and adaptedfor adsorbing and desorbing the refrigerant under predeterminedthermodynamic conditions, a cooling unit; and a circulation systemadapted for circulating the refrigerant from at least one of the firsthighly adsorptive structure and the second highly adsorptive structureto the cooling unit to provide cooling from the thermal energy sourceand to return the refrigerant from the cooling unit to at least one ofthe first highly adsorptive structure and the second highly adsorptivestructure, wherein the first and/or second substrate comprises aplurality of microchannels, wherein the microchannels are defined by atleast one of grooves in a surface of the substrate nearest the MOF andsurfaces of a plurality of microcapillaries of the substrate, whereinthe microchannels provide ingress and egress paths for the refrigerant,and wherein the refrigerant is selected from the group consisting of:acid halides, alcohols, aldehydes, amines, chlorofluorocarbons, esters,ethers, fluorocarbons, perfluorocarbons, halocarbons, halogenatedaldehydes, halogenated amines, halogenated hydrocarbons, halomethanes,hydrocarbons, hydrochlorofluorocarbons, hydrofluoroethers,hydrofluoroolefins, inorganic gases, ketones, nitrocarbon compounds,noble gases, organochlorine compounds, organofluorine compounds,organophosphorous compounds, organosilicon compounds, oxide gases,refrigerant blends and thiols.
 17. The adsorptive cooling system asrecited in claim 16, wherein the first substrate comprises a firstplurality of microchannels, wherein the first MOF is adhered to aninterior surface of the first plurality of microchannels, whereinthermal energy is conducted through an interior volume of the firstplurality of microchannels, wherein the second substrate comprises asecond plurality of microchannels, wherein the second MOF is adhered toan interior surface of the second plurality of microchannels, andwherein thermal energy is conducted through an interior volume of thesecond plurality of microchannels.
 18. The adsorptive cooling system asrecited in claim 16, wherein the first substrate comprises a firstplurality of microchannels, wherein the first MOF is adhered to anexterior surface of the first plurality of microchannels, whereinthermal energy is conducted along the exterior surface of the firstplurality of microchannels, wherein the second substrate comprises asecond plurality of microchannels, wherein the second MOF is adhered toan exterior surface of the second plurality of microchannels, andwherein thermal energy is conducted along the exterior surface of thesecond plurality of microchannels.
 19. The adsorptive cooling system asrecited in claim 16, wherein the first substrate comprises a firstplurality of microchannels, wherein the first MOF is adhered to each ofan interior surface of the first plurality of microchannels and anexterior surface of the first plurality of microchannels, whereinthermal energy is conducted through an interior volume of the firstplurality of microchannels and along the exterior surface of the firstplurality of microchannels, wherein the second MOF is adhered to each ofan interior surface of the second plurality of microchannels and anexterior surface of the second plurality of microchannels, whereinthermal energy is conducted through an interior volume of the secondplurality of microchannels and along the exterior surface of the secondplurality of microchannels,
 20. A method, comprising: forming the MOF onthe substrate to produce the product as recited in claim 1.